In the field of image analysis and display, it is common to enable a user to study image data by displaying different regions of the image data in response to navigation commands received from the user. For example, in medical field, Computed Tomography (CT) may provide three-dimensional (3D) image data of a patient which may show an anatomical structure. To enable a user such as a radiologist to study the anatomical structure, the 3D image data may be displayed to the user as a sequence of two-dimensional (2D) image slices of the anatomical structure in response to the user providing navigation commands.
To further support the user in the study of the image data, the user may be enabled to select between different display settings to optimize the display of the image data. In particular, the user may be enabled to select between display settings which, depending on the selection, cause a different sub-range of the dynamic range of the image data to be mapped to the dynamic range of the display. Effectively, by selecting a particular display setting, the user selects a particular sub-range of the dynamic range of the image data for display, with image intensities falling outside of said sub-range being typically mapped to the sub-range, e.g., by clipping. For example, the user may be enabled to select between different combinations of window width (WW) and window level (WL) parameters, with each combination of window width and window level parameters specifying a different conversion from the dynamic range of the image data to the dynamic range of the display. In the medical field, such display settings may be provided to enable optimal visualization of different types of body parts and body regions, such as different tissue types or different organs.
It is desirable to further facilitate a user in the study of image data. U.S. Pat. No. 6,127,669 describes a method which automatically calculates suitable window width and window level options when displaying an image. It is said that the method may automatically calculate optimal window width and window level setting for different structures of potential interest in the image, namely by applying a segmentation method to a histogram of the image. The method may further display a menu of window width and window level settings to allow the radiologist to browse through all structures of potential interest.
A problem of the method of U.S. Pat. No. 6,127,669 is that it insufficiently facilitates the user in studying the image data of an image volume.